CAR ENGINE IS NOT STARTING

2007 Mercedes Benz SLK350 • 6 cylinder 2WD Automatic • 30,000 miles

I HAVE SLK 350 2007 MODEL, THE CAR STARTS WHEN COOLED, ONCE YOU DRIVE THE CAR AND THE TEMPERATURE REACH 85 DEGREES, YOU SWITCH OFF THE CAR, IT IS NOT STARTING AGAIN UNTIL IT IS COLD, I CHANGE THE FUEL PUMP WITH A NEW ONE STILL THE PROBLEM ARE THERE, WE CHECKED THE GEAR SENSOR, IT IS OK, NO FAULTY MESSAGES ON THE COMPUTER, AM CONFUSED WHAT CAN BE THE PROBLEM